Raised Bed Book

Ridgerunner

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You can ask anything you wish and it will not hurt my feelings. Whether you like my answer or not is another issue. But I can truthfully say I cannot remember how many decades it's been since I had any candles on a birthday cake. But I can remember how many candles were on that cake, three. One for my first year, one for my last, and one for all the years in between.

I did some online research yesterday. I should have been doing that earlier but better late than ever. The Louisiana Extension recommendation i at least 8" of soil in a raised bed so I'll use 2x12's to make my beds. That will leave me enough room on top for mulch without it spilling out.
 

ninnymary

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Ridge, genetics do play a major role in how long we live or what we may get but lifestyle also has a major impact. My mother has survived 2 different types of cancer and a heart attack. My brother died of a heart attack at age 50. But I refuse to let those genetics get the best of me. That's why I try to live as healthy a lifestyle as possible.

There is an amazing gardener that I follow on instagram. They are vegetarians and grow almost everything they eat. Their garden is certainly bigger than mine but it's raised beds on their front and backyards. Her's are 18" and 24". Based on how much she likes them, I decided to make mine 18". It did take 2 yards of soil though.

Mary
 
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digitS'

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You should be aware of something called a "perched watertable," Ridge'. Even in the soil here with all its rocks, water becomes somewhat trapped in soil or compost simply spread on the Earth's surface.

Texas A&M soil scientists call it the "dramatic interface between two different types of soil."

... rocks.It's not that I expect to be dead, I don't expect to be able to manage much out there.
The way this is worded, my very immediate 2nd thought was "what if we have expectations 'out there.'"

I don't mean out there in the yard ... but out there in the great beyond. :)

This would be an important part of ancestor veneration. There are expectations. I can imagine some expectations I might have, some veneration cheering my days.

:) Steve
 

Ridgerunner

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Steve, I expect something similar to a "perched water table" here with my silty soil. That's a big part of why I am trying to be careful with drainage. That soil can hold water. If I try to dig it out under the raised bed and fill it with good soil that drains well I might just be digging a bathtub that holds water. I will dig it out some and get some better draining soil down there and see how it goes. I may wind up putting in some kind of French drain system but that's down the road and only if necessary. It would not be that hard to do afterwards. That's more complicated than I want to do now, once the drainage contractor does his stuff in the next two or three weeks I can get serious about getting these beds installed and at least some of them planted. My window for planting this fall is narrowing but at the least I'll be getting fresh greens. Hopefully I can get some other stuff going.
 

flowerbug

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Steve, I expect something similar to a "perched water table" here with my silty soil. That's a big part of why I am trying to be careful with drainage. That soil can hold water. If I try to dig it out under the raised bed and fill it with good soil that drains well I might just be digging a bathtub that holds water. I will dig it out some and get some better draining soil down there and see how it goes. I may wind up putting in some kind of French drain system but that's down the road and only if necessary. It would not be that hard to do afterwards. That's more complicated than I want to do now, once the drainage contractor does his stuff in the next two or three weeks I can get serious about getting these beds installed and at least some of them planted. My window for planting this fall is narrowing but at the least I'll be getting fresh greens. Hopefully I can get some other stuff going.

it's so much more to retrofit after the fact so i approve of getting the drainage and excess water flows figured out before putting things up top of it.

most of the longer term projects on this location have involved dealing with the clay and drainage. had they done this before they put in all the many gardens my efforts could have been spared many hours of labor, but at least i enjoy the digging so it isn't a complete loss. just that, i could be weeding or planting or doing many other things instead of refiguring out how to get the water situation taken care of. after this many hours and such i only have two major projects to finish, but all of this could have been taken care of 20yrs ago with some trenches, drain tubes and about another 100yards of topsoil... call it $2,000, but it would have spared about $4,000 since plus all the hours hauling things a wheelbarrow or bucket at a time or hand digging...

oh, and as a p.s. if you are doing raised beds for the larger tomatoes you do still need the root area to support the growth of such plants. figure the total volume above ground for the plants growth as that roughly needed by the plants belowground (unless you are planning on growing the patio or cherry types).
 

digitS'

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I think that just breaking down that "dramatic interface between two different types of soil" would be helpful.

I'd likely do that with with a spading fork, just loosening the soil. Perhaps by apply the new soil in two steps so that the first few inches could be worked into the existing soil a little.

Yes, the double-digging idea with French Intensive would probably not be all that good of an idea for you. But, there are a number of ways to maintain decent garden soils. Peter Chan introduced me to the idea of what some call "composting in place." For some, that just means composting plant material in paths as a mulch. It can later be moved onto the bed.

That's way too informal for me! Right now, I have corn stalks cut down and laying in one path. It's all I can do to walk through there! Cut in fairly short chunks, the tractor guy will have no problem getting through them next April. There is a possibility that I will dig out a bed and get them moved into that trench (in my easily drained soil).

When I had beds surrounded by boards, those were old cedar fence boards and they lasted about 10 years. The soil was what was already there. Top soil was only about 8" deep and moved out of the paths into the beds. Yearly, or every other year, it was moved back into the paths. In that garden was one of my compost bins. I even hauled in compostables. After a year plus, that material could be added to whatever frost-killed plants I had that fall. An 8" layer of soil returned to the bed was where the plants can be started, in the spring.

I continue doing this, even tho not in boxed beds and not in the big veggie garden. (My idea of digging out one area in the big garden would be my attempt to deal with an abundance of plant material while, hopefully, not interfering with the tractor guy's passing.

(Should be careful about my phrasing. The TG is well over 80 and likely older than all my immediate neighbors, me and The Ridgerunner ;).)

Steve
 

Ridgerunner

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Part of the reason I plan to start with cardboard but eventually switch to landscaping cloth in between and around the raised beds and cover with mulch (may take a while to get this area) is to not have to mow or weed eat that area. Part is to stop the grass from growing under the edges and coming up inside the raised beds.

But over time that mulch will rot and become a good medium for things to grow in. So I will regularly (annually I expect, I'm a lot wetter than you are so things do rot) be removing it and using it as compost. I'll have to work out that procedure. If I can get wood chips I'd like to use them, but they may not rot as fast or as uniformly as I'd like but I have a plan for that. We all know how plans work out, that's just a way to make Mother Nature laugh, but again trial and error.

I do plan to double dig underneath and mix in some stuff to help drainage. I don't think it will hurt. Even if it forms a bathtub all I have to do is dig two 16' trenches in soil that has no rocks (maybe an occasional oyster or clam shell but not many) with a couple of short side branches each and that area underneath can be drained with some variety of French drain. I'd prefer to not put in the extra work and cost now if I don't have to but a mitigation plan is ready if necessary. I would like to keep it as simple as I can.
 

flowerbug

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i've perched almost all of our raised bed gardens out back on top of extra organic materials. so if i ever do need some i just have to dig a little deeper. it provides deeper worm habitat during the really hot and really cold parts of the seasons. as of yet i have not redug an entire garden inside the fence in many years, but i do dig about 5-10% of some gardens to bury whatever scraps of organic things are left at the end of the season. so it is a pretty low till effort. similar to what @digitS' describes we do use some pathways as mulching spaces and i've dug deeper trenches in areas outside the fence to use as places to put odd bits of cut off branches or whatever that comes along.

for wood chips the decomposition rate varies by wood types and size of chips. 3-5yrs for a decent amount of decomposition is good. you may be able to scrape aside the top layer and use what has broken down underneath.

mushrooms are also sometimes seen in them. i enjoy the various fungi that show up here. you'll see more fungi in deeper layers of wood chips. you'll also see fewer weeds in them if deeper layers are used. 4-6 inches is a lot of wood chips but after
several years that will settle and be thinner.

if you find yourself getting a lot of weeds sprouting in your wood chip pathways that is usually a good sign that they are well broken down (or someone has spilled a lot of dirt there :) ). if you don't have enough time to scrape the top aside and get what's below you can also just top them off with more and let them be until you can get back to it. it's all fairly good and stable humus once it gets to the dark brown stage.

humic acid molecules are a very large one and complex, that's why they're so nice to have in the gardens, there's a lot of nooks and crannies to hold nutrients of various kinds. besides them being mild acids... i think they also act as a good buffer, but i'd have to look that up, it's been a while since i read about these. :)

now when you mention grasses growing up into your raised beds from the grassy area you currently have... it can happen for sure, but two layers of overlapping cardboard should keep most of that from happening. for shallow rooted plants that don't need to get into the subsoil/grassy level soil that's great. for deeper rooted plants you may want to remove the sod layer that you can get out of there and replace it by topsoil from some other location (but usually that also moves weed seeds around so you may not know what you are getting into there too). a few layers of cardboard may take a year or two to break down completely and hopefully by then the grass roots will have given up :) ). if not doing it a second time with the cardboard layers is good enough. i've never had any plant survive 4yrs smothered in cardboard and wood chips.

ground cover fabrics can be ok, but we've had so many of them turn into junk that has to be taken out and thrown away i'd much rather use cardboard instead.

once you have a pathway cleared of grasses and weeds you may not ever have to use cardboard again as you can use wood chips on top of wood chip humus and only top it off once in while as needed.

once weeds start showing up in the wood chip mulched areas that is the sign to me it's time to mine that humus for a garden. i first run a lot of it through the worm farm buckets to give it some extra nutrients as it is a weak fertilizer otherwise. added wth horse or rabbit manure it'd be pretty good.
 

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